This invention relates to X-ray fluorescence spectrometry, and more particularly, it relates to a cell into which a liquid sample is introduced for examination.
X-ray secondary emission or fluorescence spectrometry is recognized as a versatile instrumental technique for chemical analysis. The analyses are rapid and convenient, especially when the samples are analyzed in their original form. In such a technique, the sample is irradiated by the primary X-ray beam and excites secondary emissions of wavelengths characteristic of elements in the sample and of intensities related to their concentrations.
It is known in the art that liquid samples can be loaded in or flow continuously through a cell depending on the particulars of a given analysis. The problem experienced with known flow cells is that the face plate through which a sample is irradiated is either so thick as to absorb energy or so thin as to bend due to the pressure drop across the cell. In the latter instance, the volume of the cell is increased temporarily, resulting in a spurious X-ray count.
The presentation of a thin flowing analyte layer provides the advantages embodied in known designs such as turbulent flow which prevents separation of suspensions and reduces radiation induced sample reactions by limiting exposure duration. The thin analyte layer also provides improved X-ray signal to concentration linearity by reducing matrix absorption and enhancement effects.